The present invention relates to improvements to a measuring system such as a length measuring system which is adapted to measure at least one dimension of a test object, wherein the test object defines a resting surface which rests on a measuring surface defined by the measuring system.
A variety of measuring systems of the general type described above are known to the art (German DE-0S No. 28 21 360, German Patent No. DE-PS 10 82 422). Such measuring systems can take the form of coordinate measuring systems or length measuring systems for measuring dimensions, such as the thickness or the external end measure of a test object.
Such measuring systems include a measuring table which defines a measuring surface to support the test object. Difficulties often arise in the exact measurement of the dimensions of the test object with regard to the placement of the test object in a defined, reproduceable position on the measuring table surface. Even when the measuring table surface and the resting surface of the test object are carefully cleaned, measurement differences up to several microns have been observed. One important reason for such measurement inaccuracies is the result of air layers which may be trapped between the very flat contacting surfaces of the measuring table and the test object. In the past, it has been difficult or impossible to remove such air layers, although attempts have been made by applying high forces against the test object, thereby pressing it firmly onto the measuring table surface.